{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,13]],"date-time":"2026-06-13T01:34:30Z","timestamp":1781314470191,"version":"3.54.1"},"reference-count":39,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,12,12]],"date-time":"2020-12-12T00:00:00Z","timestamp":1607731200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European &amp; Developing Countries Clinical Trials Partnership (EDCTP2)","award":["1045-CANTAM2"],"award-info":[{"award-number":["1045-CANTAM2"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Ivermectin (IVM) is a broad spectrum endectocide whose initial indication was onchocerciasis. Although loiasis is not among its indications, IVM also exhibits antiparasitic activity against Loa loa. IVM-based preventive chemotherapies (PCs), so-called community-directed treatment with ivermectin (CDTI), have led to the interruption of transmission of onchocerciasis in some foci. A cross-sectional study was conducted in the Yabassi Health District where CDTI have been implemented since 20 years to fight onchocerciasis. All volunteers aged \u2265 5 years underwent daytime calibrated thick blood smears to search for L. loa microfilariae (mf). The prevalence of loiasis was 3.7% (95% CI: 2.2\u20136.2), significantly lower than its baseline prevalence (12.4%; 95% CI: 10.1\u201315.2; Chi-Square = 21.4; df = 1; p &lt; 0.0001). Similarly, the microfilarial density was significantly low (mean = 1.8 mf\/mL; SD = 13.6; max = 73,600) compared to baseline microfilarial density (mean = 839.3 mf\/mL; SD = 6447.1; max = 130,840; Wilcoxon W = 179,904.5; p &lt; 0.0001). This study revealed that the endemicity level of loiasis was significantly low compared to its baseline value, indicating a significant impact of IVM-based PC on this filarial disease. However, transmission is still ongoing, and heavily infected individuals are still found in communities, supporting why some individuals are still experiencing severe adverse events despite &gt; 2 decades of CDTI in this Health District.<\/jats:p>","DOI":"10.3390\/pathogens9121043","type":"journal-article","created":{"date-parts":[[2020,12,13]],"date-time":"2020-12-13T20:56:57Z","timestamp":1607893017000},"page":"1043","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Collateral Impact of Community-Directed Treatment with Ivermectin (CDTI) for Onchocerciasis on Parasitological Indicators of Loa loa Infection"],"prefix":"10.3390","volume":"9","author":[{"given":"Hugues","family":"Nana-Djeunga","sequence":"first","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"C\u00e9dric","family":"Lenou-Nanga","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cyrille","family":"Donfo-Azafack","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Linda","family":"Djune-Yemeli","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Floribert","family":"Fossuo-Thotchum","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Andr\u00e9","family":"Domche","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Arsel","family":"Litchou-Tchuinang","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jean","family":"Bopda","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"St\u00e8ve","family":"Mbickmen-Tchana","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Th\u00e9r\u00e8se","family":"Nkoa","sequence":"additional","affiliation":[{"name":"Ministry of Public Health, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"V\u00e9ronique","family":"Penlap","sequence":"additional","affiliation":[{"name":"Department of Biochemistry, Faculty of Science, University of Yaound\u00e9 1, P.O. Box 812, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francine","family":"Ntoumi","sequence":"additional","affiliation":[{"name":"Fondation Congolaise pour la Recherche M\u00e9dicale (FCRM), Brazzaville CG-BZV, Congo"},{"name":"Faculty of Science and Technology, Marien Ngouabi University, P.O. Box 69, Brazzaville, Congo"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Joseph","family":"Kamgno","sequence":"additional","affiliation":[{"name":"Centre for Research on Filariasis and Other Tropical Diseases, P.O. Box 5797, Yaound\u00e9, Cameroon"},{"name":"Department of Public Health, Faculty of Medicine and Biomedical Sciences, University of Yaound\u00e9 1, P.O. Box 1364, Yaound\u00e9, Cameroon"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Zoure, H., Wanji, S., Noma, M., Amazigo, U., Diggle, P., Tekle, A.H., and Remme, J.H.F. (2011). The Geographic Distribution of Loa loa in Africa: Results of Large-Scale Implementation of the Rapid Assessment Procedure for Loiasis (RAPLOA). PLoS Negl. Trop. 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